#!/usr/bin/env python3
"""
ESP32摄像头驱动接口模块

实现ESP32摄像头的初始化、控制和状态监控功能。
支持动态配置更改和错误恢复机制。
实现需求1.1, 1.2, 1.3：实时视频采集系统的驱动接口。
"""

import logging
import asyncio
import time
import threading
from typing import Optional, Callable, Dict, Any, Tuple
from dataclasses import dataclass
from enum import Enum
import numpy as np
from datetime import datetime, timedelta

from .esp32_camera_config import (
    CameraConfig, CameraModel, FrameSize, PixelFormat,
    ESP32CameraManager, ConfigTemplates
)

# 配置日志
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)


class CameraState(Enum):
    """摄像头状态"""
    UNINITIALIZED = "uninitialized"
    INITIALIZING = "initializing"
    READY = "ready"
    STREAMING = "streaming"
    ERROR = "error"
    DISCONNECTED = "disconnected"


class CameraError(Exception):
    """摄像头错误基类"""
    pass


class CameraInitializationError(CameraError):
    """摄像头初始化错误"""
    pass


class CameraStreamError(CameraError):
    """摄像头流错误"""
    pass


class CameraConfigurationError(CameraError):
    """摄像头配置错误"""
    pass


@dataclass
class FrameInfo:
    """帧信息"""
    timestamp: datetime
    frame_number: int
    width: int
    height: int
    format: str
    size_bytes: int
    quality: Optional[int] = None


@dataclass
class CameraStats:
    """摄像头统计信息"""
    frames_captured: int = 0
    frames_dropped: int = 0
    total_bytes: int = 0
    average_fps: float = 0.0
    current_fps: float = 0.0
    last_frame_time: Optional[datetime] = None
    uptime: timedelta = timedelta()
    error_count: int = 0
    last_error: Optional[str] = None


class ESP32CameraDriver:
    """ESP32摄像头驱动类"""
    
    def __init__(self, config: Optional[CameraConfig] = None):
        self.config = config or ConfigTemplates.balanced_config()
        self.manager = ESP32CameraManager()
        self.state = CameraState.UNINITIALIZED
        self.stats = CameraStats()
        
        # 回调函数
        self.frame_callback: Optional[Callable[[np.ndarray, FrameInfo], None]] = None
        self.error_callback: Optional[Callable[[Exception], None]] = None
        self.state_callback: Optional[Callable[[CameraState], None]] = None
        
        # 内部状态
        self._capture_thread: Optional[threading.Thread] = None
        self._stop_capture = threading.Event()
        self._frame_buffer: Optional[np.ndarray] = None
        self._frame_lock = threading.Lock()
        self._last_frame_time = time.time()
        self._frame_count = 0
        self._start_time = time.time()
        
        # 性能监控
        self._fps_counter = 0
        self._fps_start_time = time.time()
        self._fps_update_interval = 1.0  # 每秒更新一次FPS
        
    def set_frame_callback(self, callback: Callable[[np.ndarray, FrameInfo], None]):
        """设置帧回调函数"""
        self.frame_callback = callback
        
    def set_error_callback(self, callback: Callable[[Exception], None]):
        """设置错误回调函数"""
        self.error_callback = callback
        
    def set_state_callback(self, callback: Callable[[CameraState], None]):
        """设置状态回调函数"""
        self.state_callback = callback
        
    def _set_state(self, new_state: CameraState):
        """设置摄像头状态"""
        if self.state != new_state:
            old_state = self.state
            self.state = new_state
            logger.info(f"摄像头状态变更: {old_state.value} -> {new_state.value}")
            
            if self.state_callback:
                try:
                    self.state_callback(new_state)
                except Exception as e:
                    logger.error(f"状态回调函数执行失败: {e}")
    
    def _handle_error(self, error: Exception):
        """处理错误"""
        self.stats.error_count += 1
        self.stats.last_error = str(error)
        logger.error(f"摄像头错误: {error}")
        
        if self.error_callback:
            try:
                self.error_callback(error)
            except Exception as e:
                logger.error(f"错误回调函数执行失败: {e}")
        
        self._set_state(CameraState.ERROR)
    
    def initialize(self) -> bool:
        """初始化摄像头"""
        try:
            self._set_state(CameraState.INITIALIZING)
            logger.info("开始初始化ESP32摄像头...")
            
            # 验证配置
            is_valid, errors = self.manager.validate_config(self.config)
            if not is_valid:
                raise CameraInitializationError(f"配置验证失败: {errors}")
            
            # 应用配置
            if not self.manager.apply_dynamic_config(self.config):
                raise CameraInitializationError("应用摄像头配置失败")
            
            # 模拟硬件初始化过程
            logger.info("正在初始化摄像头硬件...")
            time.sleep(0.5)  # 模拟初始化延迟
            
            # 检查摄像头连接
            if not self._check_camera_connection():
                raise CameraInitializationError("摄像头连接检查失败")
            
            # 初始化帧缓冲区
            self._initialize_frame_buffer()
            
            # 重置统计信息
            self.stats = CameraStats()
            self._start_time = time.time()
            
            self._set_state(CameraState.READY)
            logger.info("ESP32摄像头初始化成功")
            return True
            
        except Exception as e:
            self._handle_error(CameraInitializationError(f"摄像头初始化失败: {e}"))
            return False
    
    def _check_camera_connection(self) -> bool:
        """检查摄像头连接状态"""
        # 在实际实现中，这里会检查I2C通信和传感器响应
        # 这里模拟连接检查
        logger.info("检查摄像头连接状态...")
        
        # 模拟连接检查延迟
        time.sleep(0.2)
        
        # 模拟90%的成功率
        import random
        return random.random() > 0.1
    
    def _initialize_frame_buffer(self):
        """初始化帧缓冲区"""
        width, height = self.config.frame_size.value
        
        if self.config.pixel_format == PixelFormat.RGB565:
            self._frame_buffer = np.zeros((height, width, 3), dtype=np.uint8)
        elif self.config.pixel_format == PixelFormat.GRAYSCALE:
            self._frame_buffer = np.zeros((height, width), dtype=np.uint8)
        else:  # JPEG或其他格式
            # 对于JPEG，我们存储解码后的RGB数据
            self._frame_buffer = np.zeros((height, width, 3), dtype=np.uint8)
        
        logger.info(f"帧缓冲区已初始化: {self._frame_buffer.shape}")
    
    def start_capture(self) -> bool:
        """开始视频捕获"""
        if self.state != CameraState.READY:
            logger.error(f"无法开始捕获，当前状态: {self.state.value}")
            return False
        
        try:
            logger.info("开始视频捕获...")
            
            # 创建捕获线程
            self._stop_capture.clear()
            self._capture_thread = threading.Thread(
                target=self._capture_loop,
                name="ESP32CameraCapture",
                daemon=True
            )
            self._capture_thread.start()
            
            self._set_state(CameraState.STREAMING)
            logger.info("视频捕获已开始")
            return True
            
        except Exception as e:
            self._handle_error(CameraStreamError(f"开始捕获失败: {e}"))
            return False
    
    def stop_capture(self):
        """停止视频捕获"""
        if self.state != CameraState.STREAMING:
            return
        
        logger.info("停止视频捕获...")
        
        # 停止捕获线程
        self._stop_capture.set()
        
        if self._capture_thread and self._capture_thread.is_alive():
            self._capture_thread.join(timeout=2.0)
            if self._capture_thread.is_alive():
                logger.warning("捕获线程未能正常停止")
        
        self._set_state(CameraState.READY)
        logger.info("视频捕获已停止")
    
    def _capture_loop(self):
        """视频捕获循环"""
        logger.info("视频捕获循环开始")
        frame_interval = 1.0 / self.config.fps
        
        while not self._stop_capture.is_set():
            try:
                start_time = time.time()
                
                # 捕获一帧
                frame = self._capture_frame()
                if frame is not None:
                    self._process_frame(frame)
                
                # 控制帧率
                elapsed = time.time() - start_time
                sleep_time = frame_interval - elapsed
                if sleep_time > 0:
                    time.sleep(sleep_time)
                
            except Exception as e:
                self._handle_error(CameraStreamError(f"捕获循环错误: {e}"))
                break
        
        logger.info("视频捕获循环结束")
    
    def _capture_frame(self) -> Optional[np.ndarray]:
        """捕获单帧"""
        try:
            # 在实际实现中，这里会从ESP32摄像头读取帧数据
            # 这里生成模拟帧数据
            width, height = self.config.frame_size.value
            
            if self.config.pixel_format == PixelFormat.GRAYSCALE:
                # 生成灰度测试图案
                frame = self._generate_test_frame_grayscale(width, height)
            else:
                # 生成彩色测试图案
                frame = self._generate_test_frame_color(width, height)
            
            return frame
            
        except Exception as e:
            logger.error(f"捕获帧失败: {e}")
            return None
    
    def _generate_test_frame_color(self, width: int, height: int) -> np.ndarray:
        """生成彩色测试帧"""
        # 创建彩色渐变测试图案
        frame = np.zeros((height, width, 3), dtype=np.uint8)
        
        # 添加时间戳效果
        t = time.time() * 0.5
        
        for y in range(height):
            for x in range(width):
                # 创建动态彩色图案
                r = int(128 + 127 * np.sin(t + x * 0.01))
                g = int(128 + 127 * np.sin(t + y * 0.01))
                b = int(128 + 127 * np.sin(t + (x + y) * 0.005))
                
                frame[y, x] = [r, g, b]
        
        # 添加帧计数器文本区域（简化版）
        frame[10:30, 10:100] = [255, 255, 255]  # 白色背景
        
        return frame
    
    def _generate_test_frame_grayscale(self, width: int, height: int) -> np.ndarray:
        """生成灰度测试帧"""
        # 创建灰度渐变测试图案
        frame = np.zeros((height, width), dtype=np.uint8)
        
        t = time.time() * 0.5
        
        for y in range(height):
            for x in range(width):
                # 创建动态灰度图案
                intensity = int(128 + 127 * np.sin(t + (x + y) * 0.01))
                frame[y, x] = intensity
        
        return frame
    
    def _process_frame(self, frame: np.ndarray):
        """处理捕获的帧"""
        current_time = time.time()
        
        # 更新统计信息
        self.stats.frames_captured += 1
        self.stats.total_bytes += frame.nbytes
        self.stats.last_frame_time = datetime.now()
        
        # 计算FPS
        self._fps_counter += 1
        if current_time - self._fps_start_time >= self._fps_update_interval:
            self.stats.current_fps = self._fps_counter / (current_time - self._fps_start_time)
            self._fps_counter = 0
            self._fps_start_time = current_time
        
        # 计算平均FPS
        uptime = current_time - self._start_time
        if uptime > 0:
            self.stats.average_fps = self.stats.frames_captured / uptime
            self.stats.uptime = timedelta(seconds=uptime)
        
        # 更新帧缓冲区
        with self._frame_lock:
            self._frame_buffer = frame.copy()
            self._last_frame_time = current_time
            self._frame_count += 1
        
        # 创建帧信息
        frame_info = FrameInfo(
            timestamp=datetime.now(),
            frame_number=self.stats.frames_captured,
            width=frame.shape[1] if len(frame.shape) > 1 else frame.shape[0],
            height=frame.shape[0],
            format=self.config.pixel_format.value,
            size_bytes=frame.nbytes,
            quality=self.config.jpeg_quality if self.config.pixel_format == PixelFormat.JPEG else None
        )
        
        # 调用帧回调函数
        if self.frame_callback:
            try:
                self.frame_callback(frame, frame_info)
            except Exception as e:
                logger.error(f"帧回调函数执行失败: {e}")
    
    def get_latest_frame(self) -> Optional[Tuple[np.ndarray, FrameInfo]]:
        """获取最新帧"""
        with self._frame_lock:
            if self._frame_buffer is not None:
                frame_info = FrameInfo(
                    timestamp=datetime.fromtimestamp(self._last_frame_time),
                    frame_number=self._frame_count,
                    width=self._frame_buffer.shape[1] if len(self._frame_buffer.shape) > 1 else self._frame_buffer.shape[0],
                    height=self._frame_buffer.shape[0],
                    format=self.config.pixel_format.value,
                    size_bytes=self._frame_buffer.nbytes
                )
                return self._frame_buffer.copy(), frame_info
        return None
    
    def update_config(self, new_config: CameraConfig) -> bool:
        """动态更新配置"""
        try:
            # 验证新配置
            is_valid, errors = self.manager.validate_config(new_config)
            if not is_valid:
                raise CameraConfigurationError(f"配置验证失败: {errors}")
            
            # 如果正在流式传输，需要重启
            was_streaming = self.state == CameraState.STREAMING
            if was_streaming:
                self.stop_capture()
            
            # 应用新配置
            if not self.manager.apply_dynamic_config(new_config):
                raise CameraConfigurationError("应用新配置失败")
            
            self.config = new_config
            
            # 重新初始化帧缓冲区
            self._initialize_frame_buffer()
            
            # 如果之前在流式传输，重新开始
            if was_streaming:
                self.start_capture()
            
            logger.info("摄像头配置更新成功")
            return True
            
        except Exception as e:
            self._handle_error(CameraConfigurationError(f"更新配置失败: {e}"))
            return False
    
    def get_status(self) -> Dict[str, Any]:
        """获取摄像头状态"""
        return {
            'state': self.state.value,
            'config': {
                'model': self.config.model.value,
                'resolution': f"{self.config.frame_size.value[0]}x{self.config.frame_size.value[1]}",
                'fps': self.config.fps,
                'pixel_format': self.config.pixel_format.value,
                'jpeg_quality': self.config.jpeg_quality if self.config.pixel_format == PixelFormat.JPEG else None
            },
            'stats': {
                'frames_captured': self.stats.frames_captured,
                'frames_dropped': self.stats.frames_dropped,
                'total_bytes': self.stats.total_bytes,
                'current_fps': round(self.stats.current_fps, 2),
                'average_fps': round(self.stats.average_fps, 2),
                'uptime_seconds': self.stats.uptime.total_seconds(),
                'error_count': self.stats.error_count,
                'last_error': self.stats.last_error
            },
            'last_frame_time': self.stats.last_frame_time.isoformat() if self.stats.last_frame_time else None
        }
    
    def reset_stats(self):
        """重置统计信息"""
        self.stats = CameraStats()
        self._start_time = time.time()
        self._fps_counter = 0
        self._fps_start_time = time.time()
        logger.info("统计信息已重置")
    
    def cleanup(self):
        """清理资源"""
        logger.info("清理摄像头资源...")
        
        # 停止捕获
        if self.state == CameraState.STREAMING:
            self.stop_capture()
        
        # 清理缓冲区
        with self._frame_lock:
            self._frame_buffer = None
        
        # 重置状态
        self._set_state(CameraState.UNINITIALIZED)
        
        logger.info("摄像头资源清理完成")
    
    def __enter__(self):
        """上下文管理器入口"""
        return self
    
    def __exit__(self, exc_type, exc_val, exc_tb):
        """上下文管理器出口"""
        self.cleanup()


class CameraFactory:
    """摄像头工厂类"""
    
    @staticmethod
    def create_camera(model: CameraModel, 
                     preset: str = "balanced",
                     custom_config: Optional[Dict[str, Any]] = None) -> ESP32CameraDriver:
        """创建摄像头实例"""
        
        # 选择配置模板
        if preset == "high_quality":
            config = ConfigTemplates.high_quality_config(model)
        elif preset == "high_speed":
            config = ConfigTemplates.high_speed_config(model)
        elif preset == "low_power":
            config = ConfigTemplates.low_power_config(model)
        else:  # balanced
            config = ConfigTemplates.balanced_config(model)
        
        # 应用自定义配置
        if custom_config:
            # 这里可以根据custom_config更新config
            if 'fps' in custom_config:
                config.fps = custom_config['fps']
            if 'jpeg_quality' in custom_config:
                config.jpeg_quality = custom_config['jpeg_quality']
            # 可以添加更多配置项的处理
        
        return ESP32CameraDriver(config)
    
    @staticmethod
    def create_auto_camera(preset: str = "balanced") -> Optional[ESP32CameraDriver]:
        """自动检测并创建摄像头实例"""
        manager = ESP32CameraManager()
        detected_model = manager.auto_detect_camera()
        
        if detected_model:
            return CameraFactory.create_camera(detected_model, preset)
        else:
            logger.error("未检测到支持的摄像头")
            return None


def main():
    """测试函数"""
    # 创建摄像头实例
    camera = CameraFactory.create_camera(CameraModel.OV2640, "balanced")
    
    if not camera:
        print("创建摄像头失败")
        return
    
    # 设置回调函数
    def frame_callback(frame: np.ndarray, info: FrameInfo):
        print(f"收到帧: {info.frame_number}, 大小: {info.width}x{info.height}, "
              f"格式: {info.format}, 字节数: {info.size_bytes}")
    
    def error_callback(error: Exception):
        print(f"摄像头错误: {error}")
    
    def state_callback(state: CameraState):
        print(f"状态变更: {state.value}")
    
    camera.set_frame_callback(frame_callback)
    camera.set_error_callback(error_callback)
    camera.set_state_callback(state_callback)
    
    try:
        # 初始化摄像头
        if camera.initialize():
            print("摄像头初始化成功")
            
            # 开始捕获
            if camera.start_capture():
                print("开始视频捕获")
                
                # 运行5秒
                time.sleep(5)
                
                # 显示状态
                status = camera.get_status()
                print(f"摄像头状态: {status}")
                
                # 停止捕获
                camera.stop_capture()
                print("停止视频捕获")
            else:
                print("开始捕获失败")
        else:
            print("摄像头初始化失败")
    
    finally:
        camera.cleanup()


if __name__ == "__main__":
    main()